Testing showed that disabling GL enforcement is not enough. Seems like gnome-session-3.9.99 suffers from severe stability issues, it crashes frequently with GL enforcement disabled. I've prepared back-ported from gnome 3.12 package: https://launchpad.net/~eugenesan/+archive/ppa/+sourcepub/4095467/+listing-archive-extra It contains a fix for GL enforcement (100_kill_gl_enforcement.patch) and upstream fixes, combined they solve the problem.
I hope package maintainers will find a way to "extract" the fix from the package above or import it to official repos. ** Changed in: gnome-session (Ubuntu) Status: Confirmed => Fix Committed -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-session in Ubuntu. https://bugs.launchpad.net/bugs/1251281 Title: gnome-flashback (metacity) fails to start without hardware acceleration, cloud/remote environments (Forwarded-X/XRDP/VNC/NX/X2GO/Chromoting) Status in “gnome-session” package in Ubuntu: Fix Committed Bug description: When trying to launch gnome-flashback (metacity) session from XRDP/VNC/NX/X2GO/Chromoting it fails with diagnostics in log: >gnome-session-is-accelerated: No composite extension. >gnome-session-check-accelerated: Helper exited with code 256 >gnome-session-is-accelerated: No composite extension. >gnome-session-check-accelerated: Helper exited with code 256 >** (process:11622): WARNING **: software acceleration check failed: Child process exited with code 1 When starting manually gnome-panel, metacity, nautilus and other components from .xsession - it works normally. Looks like - unnecessary check performed (and failed). This breaks gnome-flashback, breaking upgrade path from previous LTS and removing most sane option for cloud environments! To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-session/+bug/1251281/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp